Question

我只会发布我在.h

中的操作代码

这就是我现在所拥有的，是的，它是一个课程作业，但我认为我是唯一一个在课堂上没有Java背景且课程运行得非常快的人，所以我能做的就是获得更多的额外时间理解或当我被困住时，我只能四处询问。

-(double)performCalculation:(NSString *)operation
{
double result = 0;
    if ([operation isEqualToString:@"+"]){
        result = [self setOperand] + [self setOperand];
    }
    else if ([operation isEqualToString:@"-"]){
        double subtrahend = [self setOperand];
        result = [self setOperand] - subtrahend;
    }
    else if ([operation isEqualToString:@"*"]){
        result = [self setOperand] * [self setOperand];
    }
    else if ([operation isEqualToString:@"/"]){
        double divisor = [self setOperand];
        result = [self setOperand] / divisor;
    }
    else if ([operation isEqualToString:@"sin"]){
        double sin = sin([_operand.text doubleValue]);
        result = [NSString stringWithFormat:@"%f", sin];
    }
    [self getOperand:result];
    return result;

---------------------



i do know that it is very easy to insert the code in but i just had no idea how to do it and I am very new in this, please help!

Below is my code for the operation and the "sin" part is wrong but i don't know the correct way to apply it.


    else if ([operation isEqualToString:@"sin"]){
        double sine = sine(_operand.text doubleValue);
        result = [NSString stringWithFormat:@"%d", sine(1)];
    }

Answer 1

这样的东西？

else if ([operation isEqualToString:@"sin"]){
    double sine = sin([_operand.text doubleValue]);
    result = [NSString stringWithFormat:@"%f", sine];
}

我不确定你要做什么，但这段代码应该编译并运行。

Answer 2

更改

double sine = sine(_operand.text doubleValue);
result = [NSString stringWithFormat:@"%d", sine(1)];

到

double sin = sin([_operand.text doubleValue]);
result = [NSString stringWithFormat:@"%f", sin];

在sin.h中插入sin，tan和cos

2 个答案: